Method for controlling dehydration or water removal in drum washing machine

ABSTRACT

A method for controlling dehydration or water removal in a drum washing machine, which repetitively measures an unbalance value at different speeds during balance spin-drying for spreading laundry items before main spin-drying is performed in a drum washing machine, and senses an unbalance for forward and backward directions of a drum as well as an unbalance for the rotational direction of the drum so that the laundry items are redistributed in a relatively normal manner. Thus, since vibrations of the tub may be reduced during the spin-drying process, the spin-drying efficiency may be improved.

TECHNICAL FIELD

The present invention relates to a method for controlling dehydration(or water removal) in a drum washing machine, and more particularly, toa method for controlling dehydration in a drum washing machine, whichrepetitively measures an unbalance value at different speeds during abalance spin-drying process for spreading laundry items and before amain spin-drying process is performed in the drum washing machine, andsenses an unbalance for forward and backward directions of the drum aswell as an unbalance for rotational direction of the drum, therebyincreasing spin-drying efficiency.

BACKGROUND ART

General washing machines may be divided into pulsator washing machines,agitator washing machines, and drum washing machines, depending on thewashing method.

According to the pulsator washing machine, a rotatable pulsator at thebottom of a washing tub is rotated to generate a vortex of water,thereby spinning laundry items.

According to the agitator washing machine, when a washing rod known asan agitator in the center of a washing tub is regularly rotated, anagitating wing formed at the side of the washing rod forms a water flow.Then, as the water flows causes laundry items to come in frictionalcontact with the washing rod and the wall of the washing tub, thelaundry items are washed.

According to the drum washing machine, a cylindrical drum having aplurality of water holes therein is horizontally installed in a tub. Asthe drum is rotated, a lifter within the drum lifts laundry itemstowards an upper space of the drum, and the lifted laundry items falldownward due to gravity. Such a process is repeated to wash the laundryitems. When the drum washing machine is used, damage to laundry itemsmay be reduced, the laundry items may not get tangled, and a washingeffect of beating and rubbing the laundry items may be achieved.

Such a washing machine washes laundry items while performing a washingprocess, a rinsing process, and a spin-drying process. The washingprocess includes a water supply operation, a washing operation, and adrain operation, which are performed to remove stains, dirt, and othersoiling in laundry items using wash water containing detergent therein.The rinsing process includes a spin-drying operation, a water supplyoperation, a rinsing operation, and a drain operation, which areperformed to rinse foam and residual detergent from the laundry itemsusing clean wash water containing no detergent. The spin-drying processincludes a spin-drying operation which is performed to spin-dry thelaundry items.

DISCLOSURE Technical Problem

An aspect of the present invention provides a method for controllingdehydration (or water removal) in a drum washing machine, whichrepetitively measures an unbalance value at different speeds, forexample during a balance spin-drying process for spreading laundry itemsand before a main spin-drying process is performed, and senses anunbalance for forward and backward directions of the drum as well as anunbalance for the rotational direction of the drum, thereby increasingspin-drying efficiency.

Technical Solution

According to an aspect of the invention, a method for controllingdehydration (or water removal) in a drum washing machine includes:simultaneously agitating and balance spin-drying laundry in the drum,then accelerating a motor of the washing machine to a laundry adherencespeed; detecting a first unbalance value when the motor reaches thelaundry adherence speed; accelerating the motor to a water removal speedaccording to the first unbalance value; detecting a second unbalancevalue when the motor reaches the water removal speed; and comparing thefirst unbalance value and the second unbalance value to obtain acomparison result, and performing main spin-drying according to thecomparison result.

When the first unbalance value is less than a preset value, the motormay be accelerated to the water removal speed, and when the firstunbalance value is equal to or greater than the preset value, the methodmay continue or repeat the balance spin-drying process.

When the first unbalance value is equal to or less than the secondunbalance value, the main spin-drying process may be performed, and whenthe first unbalance value is greater than the second unbalance value,the method may repeat the balance spin-drying process.

Detecting the second unbalance value may include detecting a variationbetween forward and backward motions of a tub of the drum washingmachine.

When the variation between forward and backward motions of the tub isless than a preset variation, the main spin-drying process may beperformed, and when the variation between forward and backward motionsof the tub is equal to or greater than the preset variation, the methodmay repeat the balance spin-drying process.

The variation between the forward and backward motions of the tub may bemeasured using a distance from the tub by a distance measurement sensoron a rear surface of a front panel of the drum washing machine.

The variation between the forward and backward motions of the tub may beadditionally or alternatively measured using a distance from a magnetattached to the tub by a Hall sensor on the rear surface of the frontpanel.

Advantageous Effects

According to embodiment(s) of the invention, an unbalance value andforward and backward motions of the tub are measured at different speedsduring the balance spin-drying process for spreading laundry itemsbefore the main spin-drying process is performed in the drum washingmachine. Thus, an unbalance for forward and backward directions of thedrum as well as an unbalance for rotational direction of the drum may besensed to uniformly distribute the laundry items. Therefore, vibrationof the tub may be reduced during a spin-drying operation, which makes itpossible to increase spin-drying efficiency.

DESCRIPTION OF DRAWINGS

The above and other aspects, features and advantages of the inventionwill become apparent from the following detailed description inconjunction with the accompanying drawings, in which:

FIG. 1 is a cross-sectional view schematically illustrating a drumwashing machine in accordance with one or more embodiment(s) of thepresent invention;

FIG. 2 is a block configuration diagram illustrating a control circuitof the drum washing machine in accordance with embodiment(s) of thepresent invention;

FIGS. 3A and 3B are diagrams illustrating states of laundry items putinto the drum washing machine according to embodiment(s) of the presentinvention;

FIG. 4 is a diagram illustrating a state in which a Hall sensor isinstalled in the drum washing machine according to embodiment(s) of thepresent invention;

FIG. 5 is a flowchart for explaining a method for controllingdehydration (or water removal) in a drum washing machine according to anembodiment of the present invention;

FIG. 6 is a graph illustrating a spin-drying process of the drum washingmachine according to embodiment(s) of the present invention; and

FIG. 7 is a flowchart for explaining a method for controllingdehydration (or water removal) in a drum washing machine according to atleast one other embodiment of the present invention.

BEST MODE

Embodiments of the invention will hereinafter be described in detailwith reference to the accompanying drawings. It should be noted that thedrawings are not necessarily to precise scale and may be exaggerated inthickness of lines or sizes of components for descriptive convenienceand clarity only. Furthermore, the terms as used herein are defined bytaking functions of the invention into account and can be changedaccording to the custom or intention of users or operators. Therefore,definition of the terms should be made according to the overalldisclosures set forth herein.

FIG. 1 is a cross-sectional view schematically illustrating a drumwashing machine in accordance with embodiment(s) of the presentinvention.

FIG. 1 illustrates a state in which water is supplied to a predeterminedwater level 15 in a tub 10 which surrounds a drum 11 housing laundryitems 14 therein. When the drum 11 is rotated, the laundry items 14dipped or at least partially immersed in wash water are moved upward bythe lifter(s) 12. Then, when the laundry items 14 reach a certainposition, the laundry items 14 fall due to their own weight. Such aprocess is repeated to wash the laundry items 14.

Furthermore, a washing heater 13 for heating the wash water and/orlaundry items is installed at the bottom of the drum 11, in order toimprove washing capability and/or efficiency, and/or obtain an effect ofboiling and/or washing the laundry.

FIG. 2 is a block configuration diagram illustrating a control circuitof the drum washing machine in accordance with embodiment(s) of thepresent invention.

The control circuit includes a load cell sensor 21, a water level sensor29, a microcomputer, microcontroller or other logic circuit 20, a watersupply controller 22, a drain controller 24, a motor driving controller27, a washing heater 13, and a distance measurement sensor 30. The loadcell sensor 21 is configured to sense the weight of the laundry items 14in the drum 11. The water level sensor 29 is configured to sense thelevel of wash water within the tub 10. The microcomputer 20 isconfigured to receive the values of the load cell sensor 21 and thewater level sensor 29 and control the overall operations of the drumwashing machine. The water supply controller 22 is configured to controlthe operation of a water supply valve 23 according to a water supplycontrol signal from the microcomputer 20. The drain controller 24 isconfigured to control the operations of a drain valve 26 and/or a drainmotor 25 according to a drain control signal from the microcomputer 20.The motor driving controller 27 is configured to control the operationof a motor 28 for rotating the drum 11 according to a motor controlsignal from the microcomputer 20. The distance measurement sensor 30 isconfigured to detect forward and backward motions of the tub 10. Thewashing heater 13 serves to heat wash water according to a controlsignal from the microcomputer 20.

The operation of the drum washing machine configured in such a mannerwill be described as follows.

First, when a user opens a door of the drum washing machine, putslaundry items into the drum 11, and turns on a washing operation startswitch, the load cell sensor 21 detects the weight of the laundry items14 within the drum 11. The weight of the laundry items sensed by theload cell sensor 21 is input to the microcomputer 20.

Then, the microcomputer 20 determines an amount of water to supply byreferring to a memory table that stores predetermined values of theamount of water corresponding to a particular weight or weight range oflaundry in the drum, and outputs a control command to the water supplycontroller 22 to open the water supply valve 23. Then, the water supplyis started. While the water is supplied, the water level sensor 29 atone side of the tub 10 detects the level of water, and provides thedetected water level to the microcomputer 20. Then, the microcomputer 20determines whether or not the detected water level from the water levelsensor 29 approaches or is at a preset water level. When the detectedwater level approaches or is at the preset water level, the water supplycontroller 22 stops the water supply valve 23 to stop the water supply.

When the proper or predetermined amount of wash water corresponding tothe weight of the laundry items 14 has been supplied to the tub 10 ofthe drum washing machine, the microcomputer 20 outputs a control signalto the motor driving controller 27 according to a washing operationprogram stored therein (e.g., in the microcomputer 20), thereby causingthe motor 28 to rotate the drum 11.

When the drum 11 is rotated, the laundry items 14 are washed while beingmoved upward by the lifter 12 of the drum 11 and then falling (e.g.,into the wash water).

After the washing operation is completed, a spin-drying operation usingcentrifugal force is performed by rotating the drum 11 at high speed,thereby removing at least some of the wash water in the laundry items14.

The wash water removed from the laundry items 14 escapes to the tub 10through a large number of holes formed in the circumference of the drum11. Then, the drain valve 26 is opened and the drain motor 25 isoperated (e.g., turned on) to discharge the wash water outside of thewashing machine (e.g., through one or more pipes or tubes to an externaldrain).

In order to perform the spin-drying operation after the washingoperation and the rinsing operation, the following process may beperformed. First, a balance spin-drying process is performed to agitatethe laundry items in a side-to-side direction, thereby spreading thelaundry items. In one embodiment, balance spin-drying may comprisealternately rotating the drum 11 in forward and reverse directions, eachforward and reverse rotation being for a relatively small number ofrotations (e.g., 5 full rotations or less, 3 full rotations or less, 1full rotation or less, ½ of 1 rotation [180°], etc.). Then, the motor isaccelerated at a predetermined speed (e.g., a laundry adherence speed)so that the laundry items adhere on the inner wall of the drum, and afirst unbalance value is detected. When the first unbalance value isequal to or less than a preset value, a main spin-drying process isperformed.

FIGS. 3A and 3B are diagrams illustrating states of laundry items putinto the drum washing machine according to embodiment(s) of the presentinvention. FIG. 4 is a diagram illustrating a state in which a Hallsensor is installed in the drum washing machine according toembodiment(s) of the present invention.

In the present embodiment, the laundry adherence speed refers to a speedat which the laundry items 14 adhere on the inner wall of the drum 11and do not come off from the inner wall during a balance spin-dryingprocess. The laundry adherence speed may be from 50 to 150 RPM (e.g., avalue of from 80 to 120 RPM, such as 95 RPM). A water removal speedrefers to a speed at which foam and water contained in the laundry items14 are removed before the main spin-drying process is performed. Thewater removal speed may be from 100 to 300 RPM (e.g., a value of from125 to 250 RPM, such as 180 RPM).

Referring to FIG. 3A, the laundry items 14 may be uniformly distributedin the up and down and/or left and right sides of the drum 11, when seenfrom the front side. In this case, the motor may be accelerated at thelaundry adherence speed, and a first unbalance value is then detectedduring the balance spin-drying process. When the detected firstunbalance value is less than a preset value, the process foraccelerating the motor to the water removal speed may be performed.

When the first unbalance value is equal to or greater than the presetvalue, the method returns to the balance spin-drying process so as tospread the laundry items 14 more evenly.

On the other hand, referring to FIG. 3B, the laundry items 14 may beuniformly distributed in the up and down and/or left and right sides ofthe drum 11 as illustrated in FIG. 3A, but may be concentrated in thefront and/or rear sides of the drum 11. In this case, the firstunbalance value may be detected as a value less than preset value,because the laundry items 14 are uniformly distributed in the up anddown and/or left and right sides of the drum 11. Then, the mainspin-drying process may be performed.

However, when the RPM of the motor 28 is increased to perform the mainspin-drying process, vibration occurs in the forward and backwarddirection as indicated by the double-headed arrow, due to the laundryitems 14 being concentrated in the front and rear sides of the drum 11,with a damper 31 and a spring 32 set to an axis as illustrated in FIG.3B. As a result of such vibration(s), the tub 10 may collide with agasket 34 or cabinet front 33 and cause noise, and the washing machinemay move or become damaged.

Thus, in order to solve such a problem, the first unbalance value isdetected at the laundry adherence speed. Then, when the first unbalancevalue is less than the preset value, the motor is accelerated to thewater removal speed.

Then, a second unbalance value is detected at the water removal speed,and compared to the first unbalance value. When the first unbalancevalue is equal to or smaller than the second unbalance value, the mainspin-drying process is performed. Alternatively, when the secondunbalance value is equal to or smaller than a second preset value, themain spin-drying process is performed. Thus, it is possible to preventthe vibration caused when the laundry items are concentrated in thefront and rear sides of the drum 11.

Furthermore, the second unbalance value at the water removal speed maycomprise a variation between forward and backward motions of the tub 10.When the variation is smaller than a preset variation, the mainspin-drying process is performed. Thus, it is possible to prevent thevibration caused when the laundry is concentrated in the front and rearsides of the drum 11.

The variation between forward and backward motions of the tub 10 may bemeasured using a distance from the tub 10 by the distance measurementsensor 30 on a rear surface of a front panel 35.

That is, when the tub 10 moves in the direction(s) indicated by thedouble-headed arrow, the distance between the tub 10 and the rearsurface of the front panel 35 repetitively decreases and increases, andthe distance measurement sensor 30 measures or detects the repetitivevariation in the distance from the tub 10. In this way, the variationbetween forward and backward motions of the tub 10 may be detected todetermine an unbalance for the forward and backward directions.

Referring to FIG. 4, the variation between forward and backward motionsof the tub 10 may be detected by measuring a distance between a Hallsensor 40 on the rear surface of the front panel and a magnet 42attached to the tub 10.

That is, when the distance between the Hall sensor 40 and the magnet 42repetitively decreases and increases due to the forward and backwardmotions of the tub 10, a change of magnetic force may be sensed todetect the variation between forward and backward motions of the tub 10.Thus, the variation between forward and backward motions of the tub 10may be detected to determine the unbalance for the forward and backwarddirections.

In the present disclosure, variation(s) between forward and backwardmotions of the tub 10 can be detected using the distance measurementsensor 30 and/or the Hall sensor 40. However, the present invention isnot limited thereto, and the variation(s) between forward and backwardmotions of the tub 10 may be measured or detected using various methods.

FIG. 5 is a flowchart for explaining a method for controllingdehydration or water removal in a drum washing machine according to oneor more embodiments of the present invention. FIG. 6 is a graphillustrating a spin-drying process of the drum washing machine accordingto embodiment(s) of the present invention.

Referring to FIG. 5, the spin-drying control method for the drum washingmachine according to embodiment(s) of the present invention is performedas follows. First, in order to perform a spin-drying operation afterwashing and rinsing operations are finished, a balance spin-dryingprocess is performed. The balance spin-drying process may comprise anagitating operation in which laundry items 14 are agitated in theside-to-side direction to spread the laundry items 14 at step S10.

After the laundry items 14 are spread by performing the agitatingoperation (or a preset number of agitating operations), the motor 28 isaccelerated at the laundry adherence speed at step S20.

As described above, the laundry adherence speed refers to a speed atwhich the laundry items 14 adhere to the inner wall of the drum 11without coming off from the inner wall of the drum 11. In one example,the laundry adherence speed may be set to 95 RPM, although it may be anyvalue at which the laundry adheres to the inner wall of the drum (e.g.,from 50 to 150 RPM).

When the motor 28 or drum 11 is accelerated to reach the laundryadherence speed (e.g., section A of FIG. 6), a first unbalance value isdetected at steps S30 and S40.

Using the first unbalance value, an unbalance caused by laundry items 14concentrated in the up and down or left and right sides of the drum 11may be detected.

Then, the detected first unbalance value is compared to a preset value.When the first unbalance value is less than the preset value, it may bedetermined that the balance is maintained. Then, the method proceeds tosteps S50 and S60 to accelerate the motor 28 to the water removal speed.

However, when the first unbalance value is equal to or greater than thepreset value, the procedure returns to step S10 to perform or repeat thebalance spin-drying process.

That is, the agitating operation is performed again to uniformly spreadthe laundry items 14.

As described above, the water removal speed refers to a speed at whichfoam and water contained in the laundry items 14 are removed before themain spin-drying process is performed. In one embodiment, the waterremoval speed may be set to 180 RPM, although it is generally greaterthan the laundry adherence speed, and it may be any value at which freewater is removed from the laundry (e.g., from 125 to 250 RPM).

When the motor 28 or drum 11 is accelerated to reach the water removalspeed, that is, a section B of FIG. 6, a second unbalance value isdetected at steps S70 and S80.

When the drum 28 reaches the water removal speed, vibrations may occurin the forward and backward directions in the case where the laundryitems 14 are concentrated in the front and/or rear sides of the drum 11.However, when damping of the damper 30 is not performed in a verticaldirection (e.g., vibrations in the forward and backward directions donot necessarily cause damping by the damper 30), the second unbalancevalue may be detected as a smaller value than the first unbalance value,even though some vibration occurs.

However, when the laundry items 14 are not concentrated in the front andrear sides of the drum 11, the second unbalance value is detected as alarger value than the first unbalance value, as the damping of thedamper 30 in the vertical direction increases due to the relativelyhigh-speed rotation.

Thus, the first and second unbalance values may be compared to eachother, in order to determine whether or not the vibration occurs in theforward and backward directions.

That is, when the first unbalance value is equal to or smaller than thesecond unbalance value, it may be determined that the laundry items 14are not concentrated in the front and rear sides of the drum 11, but arerelatively uniformly distributed, and the main spin-drying process isthen performed at steps S90 and S100.

However, when the first unbalance value is larger than the secondunbalance value, it is determined that vibrations are occurring in theforward and backward directions due to concentration of the laundryitems 14 in the front and rear sides of the drum 11. Then, the methodreturns to step S10 to perform the balance spin-drying process.

That is, the agitating operation is performed again to uniformly spreadthe laundry items 14.

Alternatively, when the second unbalance value is equal to or smallerthan a second preset value, the main spin-drying process may beperformed. Thus, when the second unbalance value is equal to or greaterthan the preset value, the procedure may return to step S10 to performthe balance spin-drying process, although the second preset value may bethe same as or different from the preset value for the first unbalancedetermination.

FIG. 7 is a flowchart for explaining a method for controllingdehydration or water removal in a drum washing machine according toanother embodiment of the present invention.

In the spin-drying control method for the drum washing machine accordingto the present embodiment, a variation between forward and backwardmotions of the tub is detected as the second unbalance value detected atthe water removal speed. When the variation between forward and backwardmotions is less than a preset variation, a main spin-drying process isperformed, and when the variation between forward and backward motionsis equal to or greater than the preset variation, the procedure returnsto perform a balance spin-drying process.

The spin-drying control method for the drum washing machine according toone or more embodiments is performed as follows. First, after washingand rinsing operations are finished, the balance spin-drying process isperformed. First, an agitating operation for agitating the laundry items14 in the side-to-side direction to spread the laundry items 14 isconducted at step S110.

After the laundry items 14 are spread by performing the agitatingoperation (or a preset number of agitating operations), the motor 28 isaccelerated to the laundry adherence speed at step S120.

As described above, the laundry adherence speed refers to a speed atwhich the laundry items 14 adhere to the inner wall of the drum 11 anddo not come off the inner wall of the drum 11, and may be set to 50-150RPM (e.g., 95 RPM).

When the motor 28 reaches the laundry adherence speed, that is, thesection A of FIG. 6, a first unbalance value is detected at steps S130and S140.

Using the first unbalance value, an unbalance caused by the laundryitems 14 concentrated in the up and down and/or left and right sides ofthe drum 11 may be detected.

The detected first unbalance value is compared to the preset value. Whenthe first unbalance value is less than the preset value, it isdetermined that the balance is maintained, and the motor 28 isaccelerated to the water removal speed, at steps S150 and S160.

However, when the first unbalance value is equal to or greater than thepreset value, the procedure returns to step S10 to perform the balancespin-drying process.

That is, the agitating operation is performed again to uniformly spreadthe laundry items 14.

As described above, the water removal speed refers to a speed at whichfoam and water in the laundry items 14 are removed before the mainspin-drying process is performed. The water removal speed may be set to125-250 RPM (e.g., 180 RPM).

When the motor 28 reaches the water removal speed, that is, the sectionB of FIG. 6, a variation between forward and backward motions of the tub10 is detected as a second unbalance value, at steps S170 and S180.

As described above, the variation between forward and backward motionsof the tub 10 may be measured through a distance from the tub 10 by thedistance measurement sensor 30 on the rear surface of the front panel35.

Furthermore, the variation between forward and backward motions of thetub 10 may be measured through a distance from the magnet 42 attached tothe tub 10 by the Hall sensor 40 on the rear surface of the front panel35.

When the drum 28 reaches the water removal speed, vibrations may occurin the forward and backward directions when the laundry items 14 areconcentrated in the front and/or rear sides of the drum 11. In thiscase, as the distance between the front panel 35 and the tub 10repetitively decreases and increases, the variation between forward andbackward motions of the tub 10 is detected as a value equal to orgreater than a preset variation.

Thus, when the variation between forward and backward motions of the tub10 is smaller than the preset variation, it is determined that thelaundry items 14 are not concentrated in the front and rear sides of thedrum 11, but are uniformly distributed, and the main spin-drying processis performed at steps S190 and 200.

However, when the variation between forward and backward motions of thetub 10 is equal to or larger than the preset variation, it is determinedthat vibrations occur due to the laundry items 14 concentrated in thefront and/or rear sides of the drum 11. The procedure then returns tostep S110 to perform the balance spin-drying process again.

That is, the agitating operation is performed again to uniformly spreadthe laundry items 14.

Although some embodiments have been provided to illustrate the inventionin conjunction with the drawings, it will be apparent to those skilledin the art that the embodiments are given by way of illustration only,and that various modifications and equivalent embodiments can be madewithout departing from the spirit and scope of the invention. The scopeof the invention should be limited only by the accompanying claims.

1. A method for controlling dehydration or water removal in a drumwashing machine, comprising: agitating and balance spin-drying laundryin a drum of the washing machine, then accelerating a motor of thewashing machine to a laundry adherence speed; detecting a firstunbalance value when the motor reaches the laundry adherence speed;accelerating the motor to a water removal speed according to the firstunbalance value; detecting a second unbalance value when the motorreaches the water removal speed to obtain a comparison result; andcomparing the first unbalance value and the second unbalance value, andperforming main spin-drying according to a comparison result.
 2. Themethod of claim 1, wherein: when the first unbalance value is less thana preset value, the motor is accelerated to the water removal speed, andwhen the first unbalance value is equal to or greater than the presetvalue, the method continues or repeats balance spin-drying.
 3. Themethod of claim 1, wherein, after detecting the second unbalance value,when the first unbalance value is equal to or less than the secondunbalance value, main spin-drying is performed, and when the firstunbalance value is greater than the second unbalance value, the methodrepeats balance spin-drying.
 4. The method of claim 1, wherein detectingthe second unbalance value comprises detecting a variation betweenforward and backward motions of a tub of the washing machine.
 5. Themethod of claim 4, wherein, after detecting the variation between theforward and backward motions of the tub, when the variation between theforward and backward motions of the tub is less than a preset variation,main spin-drying is performed, and when the variation between theforward and backward motions of the tub is equal to or greater than thepreset variation, the method repeats balance spin-drying.
 6. The methodof claim 4, wherein the variation between the forward and backwardmotions of the tub is measured using a distance from the tub by adistance measurement sensor on a rear surface of a front panel of thewashing machine.
 7. The method of claim 4, wherein the variation betweenthe forward and backward motions of the tub is measured using a distancefrom a magnet attached to the tub by a Hall sensor on a rear surface ofa front panel.
 8. A method for controlling dehydration or water removalin a drum washing machine, comprising: balance spin-drying laundry in adrum of the washing machine, then accelerating a motor of the washingmachine to a laundry adherence speed; detecting a first unbalance valuewhen the motor reaches the laundry adherence speed; accelerating themotor to a water removal speed when the first unbalance value is lessthan or equal to a preset value, and repeating balance spin-drying whenthe first unbalance value is greater than the preset value; detecting asecond unbalance value when the motor reaches the water removal speed;and performing main spin-drying when the second unbalance value is lessthan or equal to a preset variation, and repeating balance spin-dryingwhen the second unbalance value is greater than the preset variation. 9.The method of claim 8, wherein detecting the second unbalance valuecomprises measuring a variation in a distance of a tub of the washingmachine from a distance measurement sensor on a rear surface of a frontpanel of the washing machine.
 10. The method of claim 8, whereindetecting the second unbalance value comprises measuring a variation ina distance of a magnet attached to a tub of the washing machine from aHall sensor on a rear surface of a front panel of the washing machine.11. The method of claim 8, wherein the laundry adherence speed is 50-150RPM.
 12. The method of claim 8, wherein the water removal speed isgreater than the laundry adherence speed.
 13. The method of claim 8,wherein the water removal speed is 125-250 RPM.
 14. A control circuitfor a drum washing machine, comprising: a load cell sensor configured tosense a weight of laundry in a drum of the drum washing machine, a waterlevel sensor configured to sense a level of wash water in the tub, amicrocomputer, microcontroller or other logic circuit configured toreceive values from the load cell sensor and the water level sensor, andcontrol operations of the drum washing machine, a motor drivingcontroller configured to control a motor that rotates the drum, and adistance measurement sensor configured to detect forward and backwardmotions of the tub.
 15. The control circuit of claim 14, furthercomprising a water supply controller configured to control the operationof a water supply valve according to a water supply control signal fromthe microcomputer, microcontroller or other logic circuit.
 16. Thecontrol circuit of claim 14, further comprising a drain controllerconfigured to control the operations of a drain valve and/or a drainmotor of the drum washing machine, according to a drain control signalfrom the microcomputer, microcontroller or other logic circuit.
 17. Thecontrol circuit of claim 14, wherein the motor driving controllercontrols the motor according to a motor control signal from themicrocomputer, microcontroller or other logic circuit.
 18. A drumwashing machine, comprising: the control circuit of claim 14, the tub,the drum, horizontally rotatable in the tub, and having a number ofholes in its circumference, and the motor.
 19. The drum washing machineof claim 18, further comprising a washing heater that heats wash wateraccording to a control signal from the microcomputer, microcontroller orother logic circuit.
 20. The drum washing machine of claim 18, furthercomprising a plurality of dampers and a plurality of springs configuredto reduce vibrations of the tub.